The prostate is a gland that is part of the male reproductive system. Its function is to produce secretions which account for about one third to one half of the composition of semen. The prostate has been described as being about the size of a walnut or a small plum.Andrology Australia: The ProstatePSA Rising: the Prostate

There are several factors that can impact the health of the prostate such as diet, exercise, certain drugs, infection and aging.Anne Arundel Medical Center: The Prostate ProgramNational Cancer Institute: What Prostate Changes Should You be Aware OfMayo Clinic: Prostate Cancer Prevention

Some common prostate diseases are benign prostatic hyperplasia, prostatitis and prostate cancerMerck Manuals: Prostate Disorders Introduction.

Prostate cancer is more common in older men. Although diagnosis and treatment of prostate cancer have improved, it is still the second leading cause of cancer deaths in men. 218,890 cases of prostate cancer were reported in 2007 according to the American Cancer Society.UrologyChannel: Prostate CancerAmerican Cancer Society: How Many Men Get Prostate Cancer